right to arm his people, march after the robber, and fight him for the
stolen oxen, as the gallant Baron of Bradwardine would fain have done.
(_Waverley_, c. xv.) Here is the right of self-defence in its full
development, including the right of private war. But in a private
individual this is an undesirable, rank, and luxuriant growth; and
when the individual comes to live, as it should be his aim to live, in
a well-organized State, the growth is pruned and cut down: he may then
defend himself for the instant when the State cannot defend him; but
after the wrong is done, he must hold his hand, and quietly apply to
the State to procure him restitution and redress. But there is no
State of States, no King of Kings, upon earth; therefore, when of two
independent States the one has wronged, or is about to wrong the
other, and will not desist nor make amends, nothing is left for it;
Nature has made no other provision, but they must fight. They must
fall back upon the steel and the shotted gun, the _ratio ultima
regum_.

2. The Lowland farmer above mentioned might be spoken of as
_punishing_ the Highland robber, _chastising_ his insolence, and the
like. This is popular phraseology, but it is not accurate. Punishment,
an act of _vindictive justice_, is from superior to inferior.
(_Ethics_, c. v., s. ix., n. 4, p. 104.) War, like other self-defence,
is between equals. War is indeed an act of authority, of the authority
of each belligerent State over its own subjects, but not of one
belligerent over the other. We are not here considering the case of
putting down a rebellion: rebels are not properly belligerents, and
have no belligerent rights.

3. The study of Civil and Canon Law flourished in the Middle Ages,
while moral science, which is the study of the Natural Law, was still